The baptized cannot pray to "our" Father without bringing before him all those for whom he gave his beloved Son. God's love has no bounds, neither should our prayer. Praying "our" Father opens to us the dimensions of his love revealed in Christ: praying with and for all who do not yet know him, so that Christ may "gather into one the children of God." God's care for all men and for the whole of creation has inspired all the great practitioners of prayer; it should extend our prayer to the full breadth of love whenever we dare to say "our" Father.
Source: Catechism of the Catholic Church (Vatican.va)